As environmentally friendly materials, carbon black and bio-oil can be used as modifiers to effectively enhance the poor high-temperature and low-temperature performance of base asphalt and its mixture. Different carbon black and bio-oil contents and shear time were selected as the test influencing factors in this work. Based on the Box–Behnken design (BBD), carbon black/bio-oil composite modified asphalt was prepared to perform the softening point, penetration, multiple stress creep and recovery (MSCR), and bending beam rheometer (BBR) tests. The response surface method (RSM) was used to analyze the test results. In addition, the base asphalt mixtures and the optimal performance carbon black/bio-oil composite modified asphalt mixtures were formed for rutting and low-temperature splitting tests. The results show that incorporating carbon black can enhance the asphalt’s high-temperature performance by the test results of irrecoverable creep compliance (Jnr) and strain recovery rate (R). By contrast, the stiffness modulus (S) and creep rate (M) test results show that bio-oil can enhance the asphalt’s low-temperature performance. The quadratic function models between the performance indicators of carbon black/bio-oil composite modified asphalt and the test influencing factors were established based on the RSM. The optimal performance modified asphalt mixture’s carbon black and bio-oil content was 15.05% and 9.631%, and the shear time was 62.667 min. It was revealed that the high-temperature stability and low-temperature crack resistance of the carbon black/bio-oil composite modified asphalt mixture were better than that of the base asphalt mixture because of its higher dynamic stability (DS) and toughness. Therefore, carbon black/bio-oil composite modified asphalt mixture can be used as a new type of choice for road construction materials, which is in line with green development.
Taking OGFC-13.2 (target porosity: 16%) as an example, this paper analyzes the shortages of current specifications on OGFC gradation design, and proposes an optimized design method for OGFC mixture. Then the Bailey method was used to detect whether the target mix can make the mixture constitute a skeleton structure. Finally, the rationality of new design method is verified through several conventional experiments with recommended gradation. New design method with clear thinking and good operability, can better guide the OGFC gradation design.
The compaction can directly affect the performance of asphalt pavement, while the mixing temperature, the molding temperature, the temperature of aggregates and the rolling times can all affect the compaction performance. The L9(34) orthogonal tests and indoor tests were used to analyze the influence of the main factors on the examination indicators. The results show that molding temperature have a significant effect on the physical and mechanical properties of SMA13 asphalt mixtures when the confidence level α is 0.10. Finally, quantitative analysis is performed to study the optimal compaction technology of molding temperature and rolling times.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.